Bundle strapping means



Nov. 30, 1965 v. GOLAND ETAL 3,220,337

BUNDLE STRAPPING MEANS Filed Dec. 17, 1963 7 Sheets-Sheet 1 Amer/ram JAMl/EL [01m 4* '8? fumum w 1965 D. v. GOLAND ETAL BUNDLE STRAPPING MEANS Filed Dec. 17, 1963 7 Sheets-Sheet 2 Mmwrow D. v. GOLAND ETAL 3,220,337

BUNDLE STRAPPING MEANS Nov. 30, 1965 7 Sheets-Sheet 5 Filed Dec. 17, 1963 G w 9 //VVEN7'0AS D WID VFFE 6'01. mvo 'SHMUEL fDWAAD SMPLTON 5 Nov. 30, 1965 D. v. GOLAND ETAL 3,220,337

BUNDLE STRAPPING MEANS Filed Dec. 17, 1965 v 7 Sheets-Sheet 4 Nov. 30,1965 D,v. GOLAND ETAL 3,220,337

BUNDLE STRAPPING MEANS Filed Dec. 17, 1963 7 Sheets-Sheet 5 //W/EA/ rams DAV/0 Vsef 644mm \SHMUfL fan/men STQPAETO/V 1965 D. v. GOLAND ETAL 3,

BUNDLE STRAPPING MEANS 7 Sheets-Sheet 6 Filed Dec. 1'7, 1965 s W N w m DAV/0 Vie: 604 4ND 7 Sheets-Sheet 7 x l 0 m D. V. GOLAND ETAL BUNDLE STRAPPING MEANS Nov. 30, 1965 Filed Dec. 17, 1963 T W \i/ |i Q N fid H M 6 i fi United States Patent 3,220,337 BUNDLE STRAPIING MEANS David Vere Goland, North Balwyn, Victoria, and Samuel Edward Stapleton, Niddrie, Victoria, Australia, ass gnors, by mesne assignments, to Signode Corporation, Chicago, Ill., a corporation of Delaware Filed Dec. 17, 1963, Ser. No. 331,223 Claims priority, application Australia, Jan. 29, 1963, 26,7 84/ 63 13 Claims. (Cl. 100-7) This invention relates to means for locating and fixing metal or other straps about a bundle of material while the bundle is held compacted between the platens of a press or the like, the respective ends of each strap being secured together to form tight loops about the bundle.

In the past, straps for this purpose have generally been manufactured to a standard length, and all operations such as positioning and fastening the straps about a bundle have been effected by hand. One form of strap commonly used is provided with a clip or buckle at one end, and after positioning such a strap around a bundle, the operator adjusts the strap length by passing the end remote from the clip or buckle, through the clip or buckle and then turns the surplus material under to fix the two ends together.

In the case of a relatively large bundle such as a wool bale, three to six straps are generally required so that the complete strapping of One bale in the above manner consumes a considerable amount of time. Furthermore, the tension obtained in each strap depends on the individual carrying out the task, with the result that it is difficult to obtain uniform or consistent tension.

It is therefore, an object of the present invention to provide improved strapping means of the kind indicated, which means functions to progressively feed, guide, tension, seal and clip, a plurality of metal straps simultaneously and which can be incorporated in a conventional pressing machine in a manner such that substantially all of the strapping operations may be automatically controlled. With such an arrangement, it is possible to control the degree of tension in the straps within fine limits.

Such strapping means are particulary adaptable for tying bundles in the form of bales of wool, and for convenience, reference will hereinafter be made to wool bales and a bale pressing machine of particular design. However, it is to be understood that use of the invention is not limited thereto but may be used with other materials and other conventional pressing machines.

In accordance with the present invention, there is provided bundle strapping means for use with a press having a pair of platens between which a bundle can be compressed, said strapping means including a strapping head mounted adjacent the platens and adapted to receive in spaced relationship the free end sections of a plurality of straps, each strap being in the form of a coil or reel and being contained in the same or separate rotatable dispenser, said strapping head including for each strap, feeding means adapted to feed the respective strap through guide means so as to completely encircle a bundle held compressed between said platens, and providing for the feed to cease after a portion of said strap adjacent the terminal end thereof passes beneath and is overlapped by another portion of said strap, gripping means adapted to receive the terminal end of the fed strap and hold the strap against complete withdrawal from about the bundle, tensioning means whereby the fed strap is withdrawn a predetermined amount so that the bundle acquires the required dimension upon being released from the compressive influence of the platens, clipping means which function to sever the strap between the overlapped portions and the coil or reel, and sealing means adapted to "ice join the overlapped portions of said strap, said gripping means thereafter releasing the terminal end of the strap in order that the bundle may be removed from the press, and control means can readily be provided whereby the various means for each strap are controlled so as to function substantially automatically in correct sequence and are synchronised so that each strap undergoes substantially the same operation at substantially the same time.

In order that the invention will be readily understood, a preferred embodiment thereof will hereinafter be described with reference to the accompanying drawings in which:

FIG. 1, is a side elevation of a typical press with which the present invention can be used, parts being omitted for convenience.

FIG. 2, is a semi-diagrammatic elevation of a preferred embodiment of the strapping means associated with the press of FIGURE 1, showing the feeding means engaged with a strap, and the tensioning means disengaged,

FIG. 3, is an enlarged view, partly in elevation and partly in section, of the tensioning means of FIGURE 2, showing it in engagement with the strap.

FIG. 4, is an enlarged sectional view taken along line IVIV of FIGURE 3.

FIG. 5, is an enlarged sectional view taken along line VV of FIGURE 3.

FIG. 6, is an enlarged end elevation of the lower platen shown in FIGURE 2, parts being omitted for convenience.

FIG. 7, is a part plan view of the platen shown in FIGURE 6.

FIG. 8, is an enlarged sectional view taken along line VIIIVIII of FIGURE 7, and showing a strap held within the guide means.

FIG. 9, is an enlarged sectional view taken along line IXIX of FIGURE 7, and showing in broken line, the strap being withdrawn from the guide means.

FIG. 10, is an enlarged sectional inverted elevation of the combined sealing and clipping tool shown in FIG- URE 2.

FIG. 11, is an enlarged sectional view of the gripping means shown in FIGURE 10, with parts omitted for convenience, and shows the terminal end of the strap being held thereby.

FIG. 12, is a still further enlarged sectional view taken along line XII-XII of FIGURE 11.

FIG. 13, is a view similar to FIGURE 12, but showing the gripping means being released.

FIG. 14, is a semi-diagrammatic side elevation of a preferred form of strapping head according to the invention.

FIG. 15, is a front elevation of the strapping head of FIGURE 14 with strapping head in its first position, parts being omitted for convenience.

FIG. 16, is a view similar to FIGURE 15, with the strapping head moving towards its second position.

FIG. 17, is an enlarged sectional view taken along line XVII-XVII of FIGURE 16.

FIG. 18, is a vertical sectional view, taken along the line XVIIIXVIII of FIGURE 10.

In the bale pressing machine shown in FIGURE 1, a press 2 is located between incoming ad outgoing conveyors 3 and 4 respectively, and includes a lower platen 6 which is adapted to be moved by a hydraulic ram 5 in a substantially vertical direction toward and away from a stationary upper platen 7. When the lower platen 6 is in its lowermost position (as shown in FIGURE 1), the platens are spaced a suificient distance apart to receive a loosely packed bale between them, and a sloped transfer chute or slide 8 is employed to direct the bale from the incoming conveyor 3, onto the lower platen 6 in a manner such that it adopts an upright position. The bale may then be compressed to a predetermined degree by moving the lower platen 6 through a suitable distance towards the upper platen 7.

Strapping of the bale is effected while the bale is held compressed between the two plantens, and, according to the present invention, a plurality of straps 9 are simultaneously applied to the bale. The straps 9 are in the form of individual coils or reels which may be contained in the same or separate dispensers (not shown) rotatably mounted adjacent the press 2. The free end sections 9a of the straps are located a suitable distance apart within a strapping head 11 which includes separate feeding, tensioning, sealing and clipping means for each strap 9, the various means being synchronised so that each strap 9 undergoes substantially the same operation at substantially the same time.

The strapping head 11 is mounted on the press 2 in a position such that it extends adjacent the sides of the two platens 6 and 7 and covers substantially the full width of the compressed bale when the lower platen 6 is in its fully raised position (as shown in FIGURE 2). The strapping head 11 preferably includes a fixed part 12 (best seen in FIGS. 1, 14, and 16) secured to the press 2, as by means of an overhanging top flange 12F which seats on the upper platen 7 (see FIGS. 1 and 14) and a movable part '13 pivotally mounted on the press as at 14 in FIG- URE 1, to move in a plane transverse to the direction of feed of said straps.

FIGS. 15 and 16 are comparative side by side views to demonstrate the relatively slight range of swinging movement of the movable part 13 about the pivot 14. The fixed part 12 of the strapping head 11 is provided with two studs or bolts 103 that project through angularly inclined slots 104 in the movable part 13 to limit the pivotal movement of the movable part 13.

Suitably spaced guides are provided in both of the platens and the strapping head for each strap so as to correctly position the straps 9 about the bale, and a guide door 16 is adapted to extend in its operative position adjacent the sides of platens 6 and 7 and cover that side of the bale opposite the strapping head 11 in order to direct the straps 9 from the guides of one platen to those of the other when the straps 9 are fed around a bale compressed between the platens. The guide door 16 is adapted to be moved by a piston and cylinder arrangement 15, and before the loading of a loosely packed bale into the press, the guide door 16 is held in an out of the way position as shown in FIGURE 1. In one particular embodiment, a bale entering between the platens 6 and 7 from the incoming conveyor 3, may be detected by a light beam for actuating the piston and cylinder arrangement 15 so as to move the guide door 16 towards the position shown in FIGURE 2. The guide door 16 in turn may actuate a solenoid or the like to cause the lower platen 6 to move towards the upper platen 7.

In one form of the invention, the strap feeding means 17 is mounted on the movable part 13 of the strapping head 11 and includes for each strap, a freely rotatable idler roller 18 and a driving roller 19 which is drivably connected to a motor 20 so as to be rotated at a substantially constant speed during operation of the machine. The free end section 911 of the strap is located between the peripheral surfaces of the two rollers 18 and 19, and the idler roller 18 is mounted for movement towards or away from the driving roller 19 so that the strap 9 may be gripped between them, or released, depending upon whether or not it is desired to feed the strap.

The driving rollers 19 for each strap 9 are secured to the same continuous shaft 21 which is supported in bearing plates 22 (FIGS. 2 and 14) secured to, and standing out from, the movable part 13 of the strapping head 11. The idler rollers 18, however, are each rotatably mounted on separate shafts 23 which are axially aligned so that only one such shaft 23 is visible in each of FIGS. 2 and 14. Each of the shafts 23 bridges between a pair of adjacent plates 22 and has its ends non-rotatably mounted within eccentric bushes 24. Thus, each of the two intermediate plates 22 shown in FIGS. 15 and 16 would be fitted with a pair of eccentric bushes and each of the endmost plates 22 would be fitted with but one. The bushes 24 are adapted for rotational movement within the plates 22, and, in each case, this movement is controlled by a solenoid 26 and connecting links 27 and 28. The link 28 is secured to the shaft 23 at one end, and is pivotally connected at its other end to the link 27 as at 29.

The strap tensioning means 31 also includes for each strap, a freely rotatable idler roller 32 and a driving roller 33 which is drivably connected to the motor 20 so as to be rotated at a substantially constant speed during operation of the machine. Furthermore, the idler roller 32 is mounted for movement towards or away from the driving roller 33 as in the case of the feeding means 17. Thus, in this particular embodiment, the constructional details of the feeding and tensioning means are substantially identical. Consequently, only the tensioning means 34 will hereinafter be discussed in detail, it being understood that the feeding means 17 is similarly constructed.

The driving rollers 33 for each strap 9 are keyed to the same continuous shaft 34 which is supported in bearing plates 36 secured to, and standing out from, the movable part 13 of the strapping head 11. Each roller 33 is provided with bosses 33a which carry bearings 37 mounted within the plates 36. It is preferred that the peripheral surface 38 of the driving roller be roughened, such as by knurling, or covered with a suitable material having good gripping qualities so that a minimum of slip occurs between the driving roller 33 and strap 9 when they are held in engagement by the idler roller 32.

The idler rollers 32, however, are each rotatably mounted on separate shafts 39 by means of bearings 41. Each shaft 39 extends through two of the plates 36 and is keyed to eccentric bushes 42 located each side of the idler roller 32. The eccentric bushes 42 are capable of rotational movement within the plates 36, and, in each case, this movement is controlled by a solenoid 43 and connecting links 44 and 46. The link 46 is secured to the shaft 39 at one end by means of a pin 47, and ispivotally connected at its other end to the link 44 as at 48.

Strap guides are provided in the strapping head 11, guide door 16, and each of the platens 6 and 7. The guides in the strapping head 11 will be hereinafter described in association with the sealing and clipping means. The guides in the guide door 16 comprises open grooves 49, each of which accommodate a pair of opposed and spaced spring influenced bars of a kind hereinafter discussed in detail with respect to the guides of the upper and lower platens 7 and 6 respectively. Each of the grooves 49 and associated bars are adapted to receive a separate strap 9, and one end of the grooves 49 and their bars are shaped as at 51 so as to direct the terminal end 92) of their respective straps into the upper platen guides.

The, guides in the upper and lower platens 7 and 6 respectively, may be substantially the same, and in one form includes open grooves 52 (see FIGURE 6), each of which receives a separate strap 9, and which each accommodate a pair of opposed and spaced spring influenced bars 53. The bars 53 are provided with inwardly directed lips 54 so as to at least partly close the open top of their respective grooves. An intermediate bar 56 secured within each groove 52, governs the minimum separation of each pair of bars 53. A plurality of transverse bores 57 provided in each intermediate bar 56 freely contain tension springs 58, the opposed ends of which are secured to the bars 53 by retaining plates 55 so as to normally hold the bars 53 as shown in FIG- URE 8.

Thus, a strap 9 is held positively within a chute 59 formed between surfaces of the bars 53 and 56 during passage of the strap 9 around a bale. The ends of the bars 53 may be flared as at 61 so that the strap 9 can enter between them as it is being tightened by the tensioning means 31, and subsequently force the bars 53 apart thereby allowing the strap 9 to emerge from the chute 59 and guide groove 52 as shown in broken line in FIGURE 9. The ends of the bars 53 and 56 are shaped as shown in FIGURE 2 so as to suitably guide the straps 9.

Further transverse bores 57a provided in the intermediate bars 56 receive tapered guide pins 53a secured to the bars 53 as shown in FIGURE 9. The pins 53a act to prevent the springs 58 being drawn hard against the walls of their respective bores 57 during tensioning of the strap 9.

In a preferred embodiment, the gripping means 62 includes a floating roller 63 located within a housing 64 having two substantially flat opposed surfaces 66 and 67, which are angularly disposed so as to converge towards an opening 68 in the housing 64 adapted to receive the terminal end 9b of a strap (see FIGURE 11). The diameter of the roller 63 gradually decreases on each side of a substantially central circumferential ridge 69 which is of predetermined radius, and a spring 71 is arranged to urge the roller 63 towards the opening 68 and also support the roller'63 so that its axis normally remains substantially parallel to the two surfaces 66 and 67, as shown in FIGURE 12.

Pneumatically or hydraulically operated combined strap sealing and clipping tools are well known in the art, and the present sealing and clipping means may comprise such a tool suitably modified for use with the machine of this invention.

One such tool 72 which is particularly adaptable for use with the present invention is shown in FIGURE 10, and includes a magazine 73 for storing a plurality of metal seal blanks (not shown). The tool 72 is secured to the movable part 13 of the strapping head 11, and is positioned so as to feed the blanks one at a time to lie across the overlapping sections 90 and 9d, of strap which are to be secured together (see FIGURE 2). A seal blank so positioned may be folded about and crimped to the overlapping strap sections 90 and 9d by means of pivotally mounted crimping jaws 74 which move towards each other under the influence of a pneumatically or hydraulically operated ram 76. The strap surrounding the bale is severed from the reserve strap material by means of one or more cutting blades 77 secured to the ram 76 adjacent to the crimping jaws 74. The blade or blades 77 may be positioned so as to sever the strap just prior to application of the seal blank, in which case a clamping pad (hereinafter described) serves to prevent relative slipping of the overlapped portions 9c and 9d in the brief interval before application of the blank.

It is preferred that the gripping means 62 be located in the base of the sealing and clipping tool 72 as shown in FIGURE 10, the position of the gripping means 62 being such that the terminal end 9b of a strap passes through the housing 64 prior to locating beneath the crimping jaws 74. Thus the overlapping portions 90 and 9d of the strap may be sealed in a manner such that a minimum of excess material protrudes out of the seal.

A clamping pad 78 may be provided in the tool 72 so as to hold the overlapped portions 9c and 9d of the strap firmly together preparatory to application of the seal blank. The pad 78 may include a stem 79 which engages with a finger 81 projecting from and movable with the ram 76. The pad 78 is influenced towards the base of the tool 72 by means of a compression spring 82, but is restrained by the finger 81 in an out of the way position as shown in FIGURE 10, during feeding of a strap. Forward movement of the ram then causes the pad 78 to engage the overlapped portions 90 and 9d prior to actuation of the jaws 74.

Suitable guide channels 83, 84 and 86 are provided in the base of the tool 72, and the channels 84 and 86 in particular are open on at least one side for a purpose hereinafter described. The first guide channel 83 (see FIGURE not shown in FIGURE 2) receives the strap 9 from the feeding means 17, and the second guide channel 84 subsequently directs the fed strap 9 into the guides of the lower platen 6. The third guide channel 86 then receives the fed strap 9 as it emerges from the guides of the upper platen 7 and directs the terminal end 9b thereof into the opening 68 of the gripping means 62.

Having now described the various components of the strapping means according to the present invention, the operation thereof is as follows. For convenience, only one strap shall be referred to in the following description of the operation. However, it is to be understood that a plurality of straps are undergoing the same operations at substantially the same time.

Initially, the lower platen 6 is at the position shown in FIGURE 1, and receives a bale from the incoming conveyor 3 and transfer slide 8. Having received the bale, the platen 6 moves upwards to compress the bale against the upper stationary platen 7. The degree of compression and movement of the platen 6 being predetermined.

During this upward movement of the platen 6, the guides in the platen are automatically aligned with their respective guide channels 84 in the tools 72, the movable part 13 of the strapping head 11 being in the position shown in FIGURE 15. This alignment is preferably achieved by having the intermediate bars 56 interconnected at one end 92 by means of a transverse bar 87 (FIGS. 6 and 7). Rollers 88 rotatably mounted at each end co-operate with cam plates 89 secured to the press 2 as shown in FIGURE 6, and rollers 91 rotatably mounted within the other end 93 of the intermediate bars 56 co-operate with cams 94 (FIG. 17) secured to the fixed part 12 of the strapping head 11.

Thus during the final part of the upward movement of platen 6, the rollers 88 and 91 co-operate with their respective earns 89 and 94 so as to align each assembly of strap guiding bars 53 and 56 transversely within their respective grooves 52 for insuring unimpaired endwise feeding of the strap around the bale.

After a bale has been suitably positioned and compressed between the platens 6 and 7, and the guide door 16 is located in its operative position as shown in FIG- URE 2, the feeding means solenoid 26 may be automatically actuated so as to turn the eccentric bushes 24 within the plates 22 and thereby move the idler roller 18 towards the driving roller 19. Thus, a strap 9 located between the rollers 18 and 19 is gripped by them and, due to the rotation of the driving roller 19, is fed into the guide channel 83, through the tool 72, and out of guide channel 84 into the guides of the lower platen 6. The platen and guide door guides progressively direct the strap 9 around the bale until the bale has been completely encircled by the strap as shown in FIGURE 2. Movement of the strap may be timed so that the solenoid is actuated to move the idler roller 18 away from the driving roller 19 and thereby release the interjacent strap, when the terminal end 9b of the strap has entered a suitable distance within the gripping means 62.

During the final part of this movement of the strap 9, the guide channel 86 functions to direct the terminal end 91) through the housing opening 68 and into engagement with the roller 63. Such engagement causes the roller 63 to move against the action of its spring 71 towards the diverging end of the surfaces 66 and 67, and the strap 9 is thus permitted to pass between the roller 63 and surface 66. The spring 71 then functions to maintain the circumferential ridge 69 of the roller 63 in contact with the strap and the surface 67.

At this stage, the tensioning means solenoid 43 is actuated to move the idler roller 32 towards the driving roller 33 and thereby grip the interjacent strap 9. In the particular embodiment illustrated, the driving roller 33 of the tensioning means 31 rotates in the same direction as the driving roller 19 of the feeding means 17, but is positioned on the opposite side of the strap.

Consequently, when the tensioning rollers 32 and 33 co-operate to grip the interjacent strap, their direction of rotation is such that they tend to Withdraw the strap from about the bale.

However, because of its contact with the roller 63, tension on the strap 9 tends to draw the roller 63 towards the converging ends of the surfaces 66 and 67 so that a wedging action results thereby increasing the grip of the roller 63 on the strap 9. Thus, the strap is firmly held by the gripping means 62 wit-h the result that the strap is withdrawn a predetermined amount to give the bale the required dimension when it expands on the release of the force exerted by the platens 6 and 7. This dimension varies, it being preferred that the inner straps be longer than the outer ones.

The tensioning rollers 32 and 33 release their influence on the strap 9 just prior to the overlapping portions 90 and 9d being joined -by a seal blank.

When the required tension has been achieved, the tool 72 is operated so that the ram 76 moves towards the strap 9. A seal blank is automatically fed into position between the crimping jaws 74 as the ram is returned from one crimping operation, so that this fed blank is carried down towards the strap 9 during the succeeding crimping operation. During the crimping operation, the following takes place in the sequence given: The gripping pad 78 abuts the overlapped portions c and 9d of the strap holding them together, the cutting blade or blades 77 sever the strap 9 close to the portion 9d, and the jaws 74 crimp the seal blank in position about the overlapped portions 9c and 9d.

As previously mentioned, the guide channels 84 and 86 in the base of the tool 72 are open on at least one side. This enables the strap portions 90 and 9a to be removed from the tool 72 in order that the tied bale may be lowered with the lower platen 6. For the purpose of this removal, the movable part 13 of the strapping head is pivoted about pivot 14 by means of a cylinder 96 which is pivotally mounted at one end 97 to the press 2. Rollers 98 rotatably mounted on the tool 72 engage the surface of the fixed part 12 of the strapping head 11 (see FIGURE 14), in order to suitably support the guide channel 84 and allow free relative movement of the movable part 13. Thus, the movable part 13 is moved pivotally through a distance sufficient for the strap portions 90 and 9d to clear the guide channels 84 and 86 (see FIGURE 16), and in so doing the gripping means 62 is released as follows.

Since the gripping means 62 is secured to the tool 72, it moves pivotally with the movable part 13 of the strapping head 11, whereas the sealed strap tends to remain stationary because of its engagement with the bale. Consequently, because of the particular configuration of the roller 63 and its contact with the strap 9, the relative movement between the roller 63 and strap 9 causes the roller 63 to tilt sideways about the circumferential ridge 69 thereby reducing its effective diameter between the strap 9 and surface 67, the result being that the wedging action is released and the strap 9 is free to move through an open side 99 of the housing 64.

Thus the strapped bale may be lowered on the platen 6 for ejection onto the outgoing conveyor 4, and the movable part 13 of the strapping head 11 is returned to the position shown in FIGURE 15 before the machine goes through a further complete cycle of operations on a following bale.

Ejection of the bale from the platen 6 may be eflfected in any known manner, such as by hydraulically operated tilting bars 101 which function to tilt the bale about one corner so that it finally tips to lie on one side on the outgoing conveyor 4.

It will be clear from the foregoing description that all operations between receiving the bale in the press 2 and ejecting it therefrom can be performed automatically by the provision of suitable solenoids, switches, and like :9 devices, and this feature combined with the fact that the plurality of straps may be tied simultaneously results in rapid and economic strapping operation.

Furthermore, the invention enables accurate control of strap tensioning thereby minimizing strap breakages, and loose and uneven strapping. Each strap tensioning means may be individually adjusted so that in the case of four straps being used for example, the outer two straps may be tied with a greater tension than the inner two thereby providing a desirable arrangement.

In addition, the particular feeding, tensioning, and gripping means employed are extremely simple yet effective.

Having now described our invention, what we claim as new and desire to secure by Letters Patent is:

1. Bundle strapping means comprising a press having a pair of vertically spaced platens between which a bundle can be compressed, conveyor means for feeding bundles to be strapped to the platens in one direction and for removing strapped bundles from the platens in said one direction, a guide door extending alongside one of the platens, means for moving the guide door vertically into and out of the path of the bundles and strapping means including a strapping head for feeding straps about bundles between said platens in a path that has a portion extending in said one direction.

2. Bundle strapping means as claimed in claim 1, said strapping head being disposed on one side of the platens, and said guide door being disposed on the other side of the platens.

3. Bundle strapping means as claimed in claim 2, and guide means on the strapping head and the platens and the guide door for guiding a strap about a bundle between the platens.

4. Bundle strapping means comprising a press having a pair of platens between which a bundle can be compressed, means for feeding a strap about a bundle between said platens, and gripping means for gripping the fed strap, the gripping means comprising means defining a pair of converging surfaces, means for feeding the strap between said surfaces, and roller means disposed between said surfaces whereby the strap moves between said surfaces freely in one directon but causes the roller means to jam between the strap and one of said surfaces upon movement in the other direction, the roller means comprising a roller having a greater circumference adjacent its middle than adjacent its ends, and means for moving said one surface laterally relative to the strap to cant the axis of said roller to release the gripping means.

5. Bundle strapping means as claimed in claim 4, said roller having a central peripheral ridge and a pair of peripheral truncated conical portions on opposite sides of the ridge.

6. Bundle strapping means for use with a press having a pair of platens between which a bundle can be compressed, said strapping means including a strapping head mechanism mounted adjacent the space between the platens and receiving the lead end sections of a plurality of straps in spaced relationship, said strapping head mechanism having a part fixed with respect to said press and a cooperating part movable with respect to the fixed part between a first gripping position and a second releasing position, each of said platens presenting cooperating guide means for each strap, feed means carried with the strapping head mechanism for feeding each respective strap from the head mechanism, through said guide means and back to the head mechanism until overlapping of strap portions occurs to form a strap loop completely encircling a bundle held compressed between said platens, gripping means carried on one of said parts to receive the lead end of the fed strap and operable to hold the same in response to said movable part being in said first gripping position and operable to release the same in response to the movable part being shifted from said first position to said second position, tensioning means for retractably withdrawing the fed strap to tension the strap loop about the bundle, clipping means to sever the strap adjacent the overlapping portions and sealing means to connect the overlapping portions of the strap.

7. Bundle strapping means as claimed in claim 6 wherein the movable part of said strapping head is pivotally mounted to part of the press so as to be capable of pivotal movement in a plane transverse to the direction of feed of the straps from said first position to said second position for releasing the gripping means and enabling the straps of a strapped bundle to be cleared from the strapping head so that the bundle may be removed from the press.

8. Bundle strapping means as claimed in claim 7, wherein the strapping head mechanism is mounted along one side of the space between the platens so as to extend across the space between said platens when a bundle is held compressed, a strap guide door carried by the press and movable to an operative position flanking the space between said platens adjacent the side opposite said one side, means for retracting said guide door to an out of the way position so as to facilitate loading and unloading of a bundle into and out of the press, and said guide door having guide means alignable with the guide means of said platens when the guide door is in operative position.

9. Bundle strapping means as claimed in claim 8, wherein the elements of the guide means in said platens and guide door includes open grooves each adapted to receive one of said straps and each having a pair of bars extending longitudinally thereof and being held spaced apart by an intermediate bar, each pair of bars being spring influenced and being shaped so as to at least partially close the open top of a chute formed between a surface of the intermediate bar and opposed surfaces of said pair of bars, said chute receiving one of said straps and said pair of bars being adapted to move apart to enable the associated strap to emerge from its chute and engage the surface of the bale upon application of a suitable tension to said strap.

10. Bundle strapping means as claimed in claim 9, wherein the intermediate bars in at least one platen are interconnected at one end by a transverse cam means on the press cooperable with said transverse bar, cam means on the fixed part of said strapping head and cooperable with the other end of said intermediate bars, whereby, during movement of said platen towards the other platen, the guide means elements in said platen are aligned with said guide means secured to the movable part of the strapping head while said movable part is in its first po sition.

11. Bundle strapping means as claimed in claim 6, wherein said gripping means includes a roller the diam eter of which gradually decreases on each side of a sub stantially central circumferential ridge, said roller being mounted in a housing for movement between two converging surfaces and being spring influenced so that the circumferential ridge normally engages both surfaces, whereby in use one of said straps is held between the circumferential ridge and one of said surfaces and tension on said strap tends to draw the roller towards the converging ends of said surfaces, and movement of said movable part of the strapping head from the first to the second position causes the roller to tilt sideways, there- 10 by reducing its effective diameter and releasing its grip on the strap.

12. Bundle strapping apparatus comprising a press having a pair of vertically spaced upper and lower platens defining a bundle space, means for elevating the lower platen towards the upper platen for elevating and compressing a bundle disposed in said space, conveyor means for feeding a bundle unidirectionally along a bundle path leading into said space on one side and leaving said space on an opposite side, means for feeding a strap to form a loop in a vertical perimeter encircling the bundle when held compressed between said platens and including a strapping head carried on said upper platen to be above said bundle path and to flank the bundle on one of said sides when the bundle is held elevated by the lower platen and means fixed relative to one of said platens and mounting a guide door for vertical movement relative to the last named platen between a position spaced vertically from the bundle space and a position flanking the bundle on the other of said sides when held elevated on the lower platen.

13. Bundle strapping apparatus comprising a press having a pair of vertically spaced upper and lower platens defining a bundle space, means for elevating the upper platen towards the lower platen for elevating and compressing a bundle disposed in said space, conveyor means for feeding a bundle unidirectionally along a bundle path leading into said space on one side and leaving said space on an opposite side, and means for feeding a strap to form a loop in a vertical perimeter encircling the bundle when held compressed between said platens and including a strapping head carried on said upper platen to be above said bundle path and to flank the bundle on one of said sides when the bundle is held elevated by the lower platen and means fixed relativeto the upper platen and mounting a guide door for linear vertical movement relative thereto between an upper retracted position and an operative position flanking the bundle on the other of said sides when held elevated on the lower platen.

References Cited by the Examiner UNITED STATES PATENTS 236,609 1/1881 Miller -218 415,288 11/1889 Boyer 100-3 X 625,307 5/1899 Adams 100-25 1,628,744 5/1927 Rose 24-1362 2,215,121 9/1940 Harvey et al. 100-26 X 2,375,769 5/ 1945 Childress et al. 2,732,792 1/ 1956 White 100-25 2,801,507 8/1957 Claus et al. 53-198 2,831,422 4/1958 Black et al 100-3 X 2,876,696 3/1959 White 100-25 2,977,872 4/1961 Allfree 100-17 2,982,063 5/ 1961 Coleman et al. 3,010,386 11/1961 Sinclair et a1. 100-25 3,019,577 2/1962 Slamar et al. 53-198 X 3,086,451 4/1963 Van Derwal 100-26 3,101,663 8/1963 Hall et al. 100-30 3,120,171 2/1964 Hall et al. 100-26 FOREIGN PATENTS 786,474 11/ 1957 Great Britain.

WALTER A. SCHEEL, Primary Examiner. 

1. BUNDLE STRAPPING MEANS COMPRISING A PRESS HAVING A PAIR OF VERTICALLY SPACED PLATENS BETWEEN WHICH A BUNDLE CAN BE COMPRESSED, CONVEYOR MEDANS FOR FEEDING BUNDLES TO BE STRAPPED TO THE PLATENS IN ONE DIRECTION AND FOR REMOVING STRAPPED BUNDLES FROM THE PLATENS IN SAID ONE DIRECTION, A GUIDE DOOR EXTENDING ALONGSIDE ONE OF THE PLATENS, MEANS FOR MOVING THE GUIDE DOOR VERTICALLY INTO AND OUT OF THE PATH OF THE BUNDLES AND STRAPPING MEANS INCLUDING A STRAPPING HEAD FOR FEEDING STRAPS ABOUT BUNDLES BETWEEN SAID PLATENS IN A PATH THAT HAS A PORTION EXTENDING IN SAID ONE DIRECTION. 